This invention relates to vehicle transmissions and especially to automatic vehicle transmissions.
Conventional automatic transmissions for vehicles employ an epicyclic gearbox and fluid coupling. It has been proposed however (SAE paper 84 0055) to employ a constant mesh gearbox of the kind having pairs of gears on parallel shafts in constant mesh with each other, together with a clutch, in an automatic transmission. A microcomputer controls actuators for the clutch and throttle and hydraulic actuators for moving the selector rod of the gearbox, in order to provide automatic operation of the gearbox in dependence upon the vehicle operating conditions.